Research Technical Report

Requiem for Ricker: Unpacking MSY

Mangel, M., B. Marinovic, C. Pomeroy, and D. Croll (2002)

Bulletin of Marine Science 70(2):763-781

ABSTRACT

Much like the Cornucopia myth of the 19th and early 20th centuries that the oceans contained limitless and inexhaustible resources, MSY as a management tool simply won't go away, regardless of evidence that 'managing for MSY' has not been effective. The present paper therefore reports an investigation of Ricker's definition of MSY, focusing on words such as "average catch," "continuously taken," and "existing environmental conditions." The investigation involved development of a model for the squid fishery in California, probably the last great open-access fishery on the west coast of the United States. Constructing the model in a step-wise fashion permitted illustration of particular points. Insight from the model leads to a deeper understanding of the definition of MSY, particularly that different methods of averaging and explicitly including risk to the stock in MSY may allow MSY to be used in the context of precautionary fishery management. Finally, results from the Third Mote Symposium that also shed light on this issue are summarized.